AAA Oregon/Idaho reported Tuesday that the average cost of a gallon of gasoline jumped 7 cents in Oregon during the past week, to about $2.68. The national average fell 2 cents to $2.29 a gallon at the same time.

Overall, Oregon’s average gasoline costs went up 16 during the past month. Oregon is one of 14 states that saw price increases, and the second-highest increase in the past week, behind Utah, which went up 9 cents. Maine had the largest price drop in the past month, down 6 cents.

Oregon drivers are paying 61 cents more for a gallon of regular than they were a year ago, according to AAA Oregon/Idaho.

Why are prices going up? AAA Oregon/Idaho blames it on maintenance at Phillips 66’s 107,500-barrel-per day refinery in Ferndale, Washington, a drop in the regional supply of crude oil and “higher production cost has applied upward pressure on fuel prices in Oregon.”

West Coast gas prices consistently rank among the highest in the country, with five states landing on the top ten list of most expensive markets this week, according to AAA Oregon/Idaho. Hawaii is most expensive at $3.07. California is in second place with $3. Washington, Alaska and Oregon round out the top five most expensive states, with Oregon in fifth place for the second week in a row, AAA Oregon/Idaho reported.

Where can you get the cheapest gasoline in the country? South Carolina ($2.03), Tennessee ($2.05 average for a gallon of regular), Alabama ($2.05), Mississippi ($2.07) and Missouri ($2.09).